Machine for planing or machining propeller blades



G. A. CLAVEY.

MACHINE FOR PLANING 0R MACHINING PROPELLER BLADES.

APPLICATION FILED OCT. 19, I920- Patented July 18, 1922.

4 SHEETS,SHEET l- FJGJ;

I Fig.2.

G. A. CLAVEY.

MACHINE FOR PLANING 0R MACHINING PROPELLER BLADES.

APPLICATION FILED OCT. 191 1920.

Patented July 18, 1922.

4 SHEETS-SHEET 2.

F'IQL4.

G. A. CLAVEYL MACHINE FOR PLANING 0R MACHINING PROPELLER BLADES. I

' APPLICATION FILED OCT. 19, 1920. 13,97.

Patented July 18, 1922.

4 SHEETS-SHEET 3.

a, A.. GLAVEY. MACHINE FOR PLANING 0R MACHINING PROPELLER BLADES...

APPLICATION FILED OCT. I9, I920.

Patented July 18, 1922.

4 SHEETS-SHEET 4.

GNM

i h tithe GILBERT AUSTIN CL-AVEY, OF BATTERSEA PARK. ENGLAND.

IVIACE-IINE FDR PLANING OB MAGI-QIIIING PROPELLER BLADES.

Application filed October 19, 1920.

chining; Propeller Blades, of which the following is a specification.

This invention concerns improvements in and relating to machines forplaning or machining propeller blades.

in object ot the invention is to improve ti type or line described inthe specification or Letters Patent No. 1901908 .c'ranted to WilliamNunn Venner nugust i39 1911, and subsequently assigned to J. StoneCompany Limiter.

A further object oi": the invention is to so improve machines oi thistype that the baclisas well as the faces of propeller blades may be qr yand accurately machined.

in machining the propeller blade, the latter is SQCLll'QCl to a rotatabe work table while the tool, which moves radially from the tip to theroot of the blade is at the same time constrained to move vertically.

T 1e invention has a'further object to proe cam mechanism for varyingthe vertical teed according to the desired varying shape of the bladesurface.

There may, for ex; nple, be a cam for v' iparting irregular motion tothe saddle or slide of each column or standard or this motion inav bcimparted more directly to the tool bar and independently of the saddleson the r lnnins.

and in order that the invention may be more readily understood,reference will be made to the accompanying drawings illus trat ng somemethod o1" cin'rying out the invention and in which Figure lis a somiicli o'l one type of machine for planing a propeler blade as isnecessary for the pur pose in view and a Figure 2 is a plan of thecolumns or standards and some of the parts thereon.

igures an n 7' setting out the cam.

di I ms to Figure an elevation of amachinc with a modified camarrangement.

.1 igurc detail in sectional elevation showing; another modification andl ignre ill a similar view ol detail of yet another modification.

Specification of Letters Patent.

part sectional elevation of o and 7 are e iplanatory Patented July 18,1922.

Serial No. 418,022.

columns or standoverhead horizontal frame member or bridge piece (Z,each standard carrying a vertical slide or saddle marked 6 and frespectively, one vertical column 6 being arranged near the middle oilthe work table and the other 0 to one side of the 'work table.- Betweenthe vertical saddles c and f is pivotally mounted at 5/ g, a crosshead,bar or slide which coinprises two parts g, 9*, slidable upon one anotherthe part g carrying a tool saddle hereai the vertical saddle c and thepart g is at one end pivoted at to the vertical saddle 7", while itsother end engages guides in the art- 9 so as to be capable ofendwisemove,

ment with respect to the said part, and allow of extension orcontraction of the distance between the pivots g f when the crosshead orslide is moved from a horizontal to an angular position or when theangular posit on is varied during the adjustment of said crosshead.Mounted on the part 9 of the crosshead or slide is a saddle h which isadapted to carry the tool bari and is hereinaft r referred to as thetool saddle This tool saddle fl is caused to reciprocate on the slide orc sshead by any suitable or known means that cuts are taken on thesurface of the propeller blade in the radial direction il l'fliil tip toroot and the feed caused by the combined intermittent and irregularmovement of t 1e saddles c and j on the columns Z) and c and the slowinteri'nittent but uniform movement of the table a, is in the directionThe two vertical saddles e and f areadag ited to be moved or tedvertically by means oi? screws 7c Z engaging nuts connected with thesaid slides. The rate of movement or vertical feed to be given toreferred to is pivoted at g "to I bridge-piece or stretcher (Zconnecting the said standards, and now to be described.

A bevel wheel mechanism (comprising a shaft or, driven from anyconvenient source of power, and bevels 0 and p suitably mounted inbearings) conveysthe feed from the main driving mechanism to a worm gand worm wheel 1*, the worm wheel being fixed centrally on a shaft 8arranged parallel with the top frame member, bridge-piece or stretcherd. at each extremity of the worm wheel shaft 3 is fixed a worm t whichengages a worm wheel a or a fixed to and below a cam disc 4) or a havinga cam groove 12 or 11 formed therein.

In each cam groove o or '0 is a pin to or to fixed to slide 3 or yslidable in a guide way 2 or 2, so that movementof the cam will causethe slide 3/ or y to move backwards or forwards in its slide way a or a,each slide having formed thereon a rack 10 or 11 adapted to operate bypinions 12 or 13 a train of gear wheels 1-1 or 15, shafts 16, or 17,worms 18 or 19 and worm wheels 20 or 21 connected with one of the screwsor Z operating the vertical slides or saddles e and 7" respectively.

Thus the cam a will operate the vertical saddle 6 near the root of thepropeller blade which is fixed to the work table a, and the other cam vwill operate the vertical saddle f near the tip end of the propellerblade. If now the shape of these cam grooves he so proportioned as togive the correct amount of downward or upward feed to the verticalslides and through them to the crosshead or slide 9* 9 and tool bar 6 atall points of the reciprocatory movement of the tool, and the bladesurface will he machined accordingly.

The shape of the two cams is arrived at as follows: The face of apropeller blade is a part of a helix, and for the purpose of designingthe cams, and as shown in Figure 3, the radius of the helix is taken asbeing from the centre A of the work table to the pivot or hinge g of thecross slide, the screw 70 actuating the vertical slide near the root endof the blade being arranged near the centre of the table, and so thatthe tool in may move in a radial direction from the tip of the propellerblade towards the centre or-axis of the propeller.

The outline of the blade is set out expanded or as a flat surface(indicated by the line 21, Figure 3), and is then divided out into anumber of radial divisions, from centre A of boss to tip 22, of say (9each. It will be assumed that the blade area comes within ten of thesedivisions or T of one complete helix, five on each side of the centreline A-A, but, seeing that the blade is expanded, it appears to startoutside of the lines 6 on each side of the centre line. The lines 23point to the lines 5 where the edges of the blade are really situated.The chain .line QLindicates the root section. On the l ft hand side ofthis figure, the line 25 represents the thickness of the blade at theroot. The line 26 represents the centre line or axis of the propellerand the point A represents the imaginary centre line of the screw 70 forraising and lowering the sad dle b.

The cross sections at root and tip are now set out on their respectivepitch angles to the same scale as in Figure 4: (below the diagram Figure3) the tip section being extended to the width of the ten sections of7-}-, or live sections on either side of the centre line A. From thesetwo diagrams can now be obtained the relative vertical distance from anygiven point on the centre line to the back of the blade on any of theseveral radial lines marking the divisions of 7%".

A further diagram Figure 5 is now drawn to the same scale setting outthe vertical distances, for example, from line 6, that is the linemarking the next division 74 on either side of the centre line, topoints on the lines 2st and representing the root and tip sections, asdetermined from the diagram Figure 41-, and these are et out relativelyto each other and to the centre line of the propeller boss and thecentre line of the cross head pivotal connection 9 lines being d awn toconnect the similar points on root section 24rand tip section 22 andproduced on either side to the lines marking the boss centre line A. andcross head pivot centre line The vertical distances shown on the linesmarking the boss centre line A and the cross head pivot centre line gwill give the amount of feed to be in'iparted to the vertical saddles eand f at the ends of the cross head g 9*.

These distances are set off on the cams Figures 6 and 7 to give the formof the cam groove.

In setting out the cams, their surfaces will be divided into the samenumber of divisions as that employed for setting out the diagrams, whichis, in this case, six on either side of the centre line, or twelvealtogether, the angle between the divisions being thus 30 or four times74 In view of this it will be understood that it will be necessary forthe. rate of revolution of the cam plate to be four times that of'thetable carrying the work. Figure 6 is a diagram showing the cam e foroperating theleading screw is of the saddle for the root or boss end ofthe propeller blade while the diagram Fig-- ure 7 shows the cam 41 forcommunicating motion to the leading screw Z of the saddle 7' at the tipend of the blade.

Or as shown in Figure 8, instead of causing the saddles e and f each tobe operated by a cam, there may he one cam which operates a bar pivotedto the cross head or bar slide g 9* the tool bar being connected to theslide bar, and so mounted as to be capable of sliding more or lessvertically in the tool saddle, while reciprocating with the saddle dueto the inclination the slide bar is caused by the cam, to assume inrelation to the crosshead. The result is, as in the previous instance,the propeller blade is planed or machined in manner to approximatelyproduce a helix, but the propeller blade is left much thicker at theroot than at the tip when the operation has been performed. As in thefirst construction described, the machine comprises a circular table(not shown) adapted to be rotated at a uniform intermittent speed by anywell-known means, a column or standard Z), mounted above the middle ofthe table having a saddle and leading screw 74, a column or standard 0,mounted outside of the periphery of the table, having a saddle f and aleading screw Z and a cross head or slide 9 pivotally and adjustablyfixed at both ends at g and to the said saddles e and f. The tool bar iiis in this case not fixed to the reciprocating tool saddle h but isadapted to slide freely in a more or less upright direction in a guidea" adjustably fixed to the said saddle. Mounted on the cross head g is aslide bar 27 pivoted at 28 to a slidable block 29, adapted to beadjusted along the crosshead and firmly bolted in position. If desired,the top or facing of the crosshead is provided with a rule or scale fordetermining the correct distance of mounting the centre pin 28 from thecam which is adapted to actuate or move the other or free end of theslide bar 27. The slide bar carries a small saddle or block 30 adaptedto slide freely along the slide bar 27 and the tool bar 2' is pivotallyconnected to the said small saddle 30. The free end of the slide bar hasadjustably mounted thereon a bracket- 31 carrying a stud and a bowl orroller 32 (indicated in dotted lines) which is adapted to roll incontact with a cam 33. This cam is revolubly mounted on a saddle 34L-havii'ig a guide to limit the movements of the slide bar The saddle 34:is slidably mounted on a vertical column or standard 36 convenientlyfixed to a wall or masonry. The saddle is provided with a nut in whichengages the leading screw 37 and this is driven by providing it with aworm wheel mounted in the casing 38 and driven by an extension 8 of theshaft s which similarly communicates motion to the saddles c and f. Thebowl 32 for the cam 33 is kept up against the latter by a chain or rope39 attached at one end to the slide bar 27, passing over pulleys 40 andll and having at its other end a weight $2. The cam is con venientlydriven by an overhead shaft 43. which by another shaft 4A (receivingmotion wheel l8 has bolted or fixed thereto the cam,

33 and, when the latter revolves, it causes the slide bar to rock in avertical plane and in rocking it also moves the tool bar a" up and downwith it, the tool bar also traveling back and forth with the tool saddlewhich is reciprocated in any well known manner. The cam being rotated atthe same time as the table, the reciprocation of the tool and thevertical movement of the latter, all occur simultaneously and the backsof propeller blad s may be planed or machined in a period which ismaterially shorter than when this work is performed by hand, added towhich the operation is performed with mathematical accuracy and thesurface is uniform.

Referring to Figure 9, the construction differs from that just describedinasmuch as the weight 48 is hung on the end of the slide bar 27 and thecam bowl a9 rests on the cam 33.

In Figure 10 the construction of the cam 33 and slide bar is generallythe same as described with reference to Figure 8, but the cam isprovided with a projection 51 which when near the end of the stroke ofthe tool bar lifts the latter and with it the tool clear of the work sothat it is not necessary to cut a groove or landing into which the toolmay come at the end of its cutting stroke and which necessarily thenrequires further treatment to finish off the blade at its rootandnioreover, the tool may also finish the fillet or radius at the rootof the blade where it merges into the boss. Although both of theconstructions of machines illustrated are of the type in which the cutis in the radial direction from the tip towarcs the root of the.propeller blade and the combined motion of the rotating work table andthe vertical movement of the saddles on the columns or standards producethe pitch, it will be evident that the invention may also be applied toother types of machines in which, for example. the cuts are takenconcentrically. the table is adapted to oscillate, and, the tool to recprocate vertically and to be,

fed in the radial'direction.

Suitable clutches and other adjuncts such as means for adjusting by handand so on are employed wherever advisable. but their arrangement formsno part of the invention and provision thereof will be apparent to thoseskilled in the art to which this invention appertains.

I claim 1. An apparatus for machining propeller blades and like helicalsurfaces, comprising a power driven revoluble table, a tool radiallyreciprocable across said table, a tool feed mechanism adapted forfeeding said tool perpendicidarly to the table and in the direction otthe pitch, and cam control mechanism operative upon said tool feed forchanging' said feed in accordance with the varying shape of the helicalsurface.

2, Apparatus for machining propeller blades and like helical surfaces,comprising a revoluble work table, tool holding means reciprocableradially of said table, tool teed control means extending radially oisaid table but inclined to the plane thereof, and operative to feed saidtool perpendicularl to said table, and power driven cam mechanism inoperative connection ith said tool feed control means and operative toalter the relation with said table of said tool feed control means forthe purpose oi causing the tool to move vertically according to thevarying shape of the helical surface.

3. An apparatus for machining propeller blades and like helical surfacescomprising a revoluble worktable, driving micl'ianism therefor, a cross:head, means to raise or lower both ends of the said crosshead inrelation to the work-table and a tool-saddle slida-ble on the saidcrosshead, a cam device for cont-rolling the feed oi? the tool forcausing the tool to be vertically adjusted before the commencement ofeach cutting stroke according to the required varying shape of thehelical surface.

l. An apparatus tor machining propeller blades and like helical surfacescomprising, in combination, revoluble work-table, driving mechanismtherefor, a cross-head, means to raise or lower both ends oi the saidcrosshead, a tool-saddle slidable on the said cross head, mechanism tocause the said toolsaddle to reciprocate on the said crosshead, atool-bar on the tool-saddle slidable in a direction approximatelyperpendicular to the work-table and a cam device for controlling themovement of the said tool-bar and to cause it to be vertically adjustedin relation to the said tool-saddle before the commencement of eachcutting stroke.

5. An apparatus tor machining propeller blades and like helical suriacescomprising in combination a revoluble work-table, driving mechanismtherefor, two vertical columns, a saddle on each column, a crossheadconnecting the saddles, a tool-saddle reciprocally mounted on the saidcrosshead, an adjustable guide mounted on the said tool-saddle, a toolbar adapted to slice in the said guide, a slide bar pivoted to thecrosshead and slidably carrying thereon the said tool bar, a cam adaptedto engage the said slide bar and mechanism for operating the said cam,the said mechanism being driven in positive relation to the drivingmechanism for rotating the revoluble-work table.

(3. An apparatus for machining propeller blades and like helicalsurfaces comprising,

in combination, a revoluble work-table, driving mechanismtherefor, twosaddle adjusting vertical cohnnns, a vertical fecdscrew in each column,driving gear for the said teed-screws, a saddle on each column inoperative engagement with one ot the said feed screws, a crossheadconnected'to the said saddles, a tool saddle, slidable on the saidcrosshead driving mechanism for causing the said tool-saddle toreciprocate on the said crosshead, an adjustable guide mounted on thesaid tool saddle. a tool-bar adapted to slide in the said guide, a slidebar pivoted at one end to the said crosshead, a slide mountedon the saidslide bar and to which the tool bar is pivotally connected, a camadapted to engage the said slide barn-and mechanism for operating thesaid cam, the said mechanism being driven in positive relation to thedriving mechanism tor rotating the revoluble table.

7, An apparatus for machining propeller blades and like helicalsurfaces, comprising, in combination, a revoluble work-table, drivingmechanismtherefor, three saddle adj usting vertical columns, a vertical.teed. screw in each column, driving mechanism for the sail teed screws,a saddle on each vertical column in operative,engagement with one ofthe-said teed screws, a crosshead connect-' ed to two ot the saddles, atool-saddle slidable, on the said crosshead, driving mechanism torcausing the said tool-saddle to reciprocate on the said crosshead, anadjust-- able guide mounted on the said tool-saddle, a tool bar adaptedto slide in the said guide, a slide bar pivoted at one end to the saidcrosshead, a slide mounted on the said slide bar and to which thetool-bar is pivotally connected, a cam mounted on the saddle of thethird vertical column and adapted to engage the said slide bar anddriving mechanism. for the said cam.

8. An apparatus tor machining propeller blades and like helical surfacescomprising, in combination, a. revoluble work-table, driving mechanismtherefor, a crosshead, means to raise or lower both ends of the saidcrosshead in relation to the work-table, a tool saddle slidable on thesaid crosshead, mechanism to cause the said tool-saddle to reciprocateon the said crosshead, a tool bar on the tool-saddle, slidable inadirect-ion approximately perpendicular to the worktable, a cam devicefor controlling the movement of the said tool bar in relation to thesaid tool saddle, and for lifting the tool bar when near the end of theworking stroke, and mechanism for operating the said cam.

GILBERT AUSTIN CLAVEY.

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